There is a particular kind of room that has almost everything right and still feels like it’s missing something. The furniture is good, the color works, but the sofa looks unfinished and nothing quite connects. Usually the answer is a long cushion. Not more cushions, just the right one sitting across the back of a sofa or along a window seat, holding the whole arrangement together. It sounds small. It is not small. A lumbar or bolster in the right fabric and proportion does something that scatter cushions alone cannot, it gives a scheme a spine. We’ve been looking at long cushions specifically because they’re easy to overlook and surprisingly hard to find when you actually go looking. Interesting textures, colors that bridge rather than shout, sizes that actually suit a standard sofa rather than swamping it. These are the ones we’d reach for when a room is close but not quite there yet.